I've used Supabase for some production level projects, and it's seriously a very good starting point which you can scale up to mid-tier levels. Brand new ones with no customers can easily leverage their free tier.

Gotta build the prototype on something eventually. It’s a solid OOTB tech stack. Lets you focus on building the business with peace of mind. Not fiddling with servers etc.

For the past several years, “startup” meant at least 5 years in operation with over $1 billion valuation.